Sliding door latch hub



March 23, 1965 F. J. RUSSELL 3,174,783

sLInING nooR LATCH HUB Filed Nov. 9, 1962 INVENTOR. FRED J.' RMSSELL ATTO 2N E'YS lldfl Patented Mar. 23, 1965 3,174,7@3 SLHDING DQR LATCH H Fred Il'. Rossell, 3300 Don Felipe Drive, Los Angeles, Calif. Filed Nov. 9, 1962, Ser. No.. 236,540 4 Claims. (Cl. 292-103) The invention is directed to what is commonly known to the trade as a sliding door latch. More particularly, the invention has reference to a certain portion of the latch mechanism, namely, employment of a low-friction component at a location where the wearing effect is at a maximum, thereby to improve the performance of the mechanism.

Because of recent trends in construction, sliding doors have been employed in substantially greater quantities than has been experienced in the immediate past. A variety of types of sliding door hardware have accordingly been developed to meet the modern trend of compactness, neatness, ease of installation, and relatively low cost; but in attempting to incorporate all of these qualilications into a sliding door latch, some needed characteristics have been sacrificed. Although some locks operate in a perfectly satisfactory manner when new where they depend upon metal to metal frictional engagement of certain of the working parts, the frictionally engaging surfaces frequently pit and wear to the extent that the latch becomes unsatisfactory and often inoperable after a relatively short period of use.

It is therefore among the obiects of the invention to provide a new and improved sliding door latch wherein certain frictionally engaging parts are constructed of lowfriction material thereby to greatly improve the lifetime of the mechanism.

Another object of the invention is to provide a new and improved sliding door latch wherein parts, which because of practical necessity must be made of strong but inexpensive material such as sheet metal, are altered slightly so as to accommodate a low-friction material such as one of the currently commercially available synthetic plastic resins thereby to provide an assembly retaining all of the necessary strength of the metal part but adding to the metal part a low-friction Contact which minimizes the wear of the part upon other portions of the device.

Still another object of the invention is to provide a new and improved sliding door latch mechanism and in particular the hub and latch hook members of the mechanism constructed in such fashion that they are combined so as to employ a metal latch and a hub of one of the current synthetic plastic resins in such a cooperative relationship that the necessary and desirable features of both are retained in a fashion enabling them to work together in the lock mechanism and against a spring element thereby to minimize wear and improve the lifetime of operation of the device.

Still another object of the invention is to provide a new and improved sliding door latch mechanism of the kind hereinabove made reference to which is simple in its construction, easy to assemble, moderate in cost, and quiet in its action.

With these and other objects in view, the invention consists in the construction, arrangement and combination of the various paits of the device, whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims and illustrated in the accompanying drawings.

In the drawings:

FIGURE l is a side-elevational View of the exterior of a sliding door latch showing certain of the parts by broken lines in unlocked position.

FIGURE 2 is a longitudinal sectional view of the device of FIGURE l showing the latch in locked position.

FIGURE 3 is a fragmentary longitudinal sectional view showing certain of the operating parts in the interior in the position they would have in unlocked position.

FIGURE 4 is a fragmentary longitudinal sectional view similar to FlGURE 3 but showing the same parts in locked position.

FIGURE 5 is a fragmentary cross-sectional view taken on the line 5 5' of FIGURE 3.

FIGURE 6 is a top view partially broken away showing the door latch mechanism mounted in a door as in FIG- URE 1.

FIGURE 7 is a fragmentary end-elevational view taken on the line 7--7 of FGURE l.

FIGURE 8 is a fragmentary, transverse, sectional view of a second form of the invention.

FGURE 9 is a fragmentary, side-elevational view taken on the line -9 of FlGURE 8.

In an embodiment of the invention chosen for the purpose of illustration, there is shown a section of sliding door itl having a recess lll therein adapted to receive a housing of the sliding door latch indicated generally by the reference character l2. Mounting plates 13 and 14 on respectively opposite sides are shown overlying the housing and also overlying portions of the door to which they are attached by means of screws 15. A face plate 16 overlying an edge i7 of the door is secured by appropriate means (not shown) to anges 18 of the housing. Lips 19 of the respective mounting plates are adapted in the usual fashion to overlie the outside surface of the face plate, these features being of substantially conventional construction.

ln the form of invention here under consideration, a linger hold Ztl provided with a hook 2l is tiltably mounted by means of a pin 22 in side walls 23 and 24 of the housing. The linger hold, when not extended, substantially closes an opening 25 in the face plate 16, there being a short section 2o of the linger hold located above the pin 22 to assist in tilting the finger hold outwardly when it is to be used.

The side walls 23 and 24 forming the housing 12 may preferably be of metal stampings dished so as to provide a chamber 27 within which operating parts of the lock mechanism can be located.

A latch hook member or catch 30 is pivotally mounted within the chamber 27 by means of a hub member 31. The spindle assembly enables a latch hook member to be tilted between the broken line position of FIGURE l, namely, a withdrawn or unlatched position, to a solid line extended or latched position as shown in FIGURE 2. It is, of course, desirable to have the latch hook member releasably retained in one or another of these two positions and this is accomplished by employment of a spring 32.

More particularly, the hub member comprises a central hub 33 having a noncircular passage 34 extending therethrough which is adapted to receive at one end a shaft 3S of a turn 36 and at the other end a shaft 37 of a button 33. Snap rings 3% hold the turn and button in rotatable positions respectively on the mounting plates 13 and 14. The hub is rotatably secured in holes 40' and 41 respectively in extensions 42 and 43 of the side walls 23 and 24.

From the foregoing description, it will be clear that by rotating the turn 36 the hub and, of course, the entire hub member can be rotated from that particular side of the sliding door latch. The purpose of rotation is to manipulate the latch hook member 3G, shifting it from retracted to extended position and then back again. This, of course, requires a nonrotatable or lixed connection between the o hub member and especially the hub and the latch hook members.

In the form of invention chosen for the purpose of illustration, a central section 45 of the hub has a noncircular form as shown to good advantage in. FIGURES 3 and 4. The central section fits snugly in an aperture 46 of corresponding shape and size in an inner arm 47 of the latch hook member. It is noteworthy that the hub is constructed preferably of one of the commercially available synthetic plastic resins of which nylon is a typi- -cal example. In the chosen form of device, the shaft 35 and turn 36 are of the same plastic material as are also the shaft 37 and button 3S. Accordingly, a boss 48 on the central section 45 of the hub is an integral portion of the hub and is of the same synthetic plastic resinous material.

Cooperating with the 4boss d8 is a configuration 52 of the spring 32. One side 53 of the configuration is adapted to be pressed against by the boss when the latch hook member is in retracted position and another side 54 is adapted to be pressed against by the same boss when the latch hook member is in extended or latched position.

Although the boss will operate successfully irrespective of Where on the hub it lmay be located, special advantage accrues by having the boss extend outwardly through a recess 49 in the arm 47 which connects between the aperture 46 and the exterior of the arm. Sections 5t) and 51 immediately adjacent the recess 49 overlie a portion of the central section 45 of the hub to provide the necessary strength and to assist in holding the hub nonrotatably secured within the latch hook member.

In order to mount and retain the spring in position, resort is had to a substantially conventional securing means, namely, the provision of holes 55 in respective legs 56 of the spring into which `extends tabs 57 which are actually portions of the sheet metal side Walls 23 and 24.

In order for the spring itself to be inexpensive as well as effective, it is preferably constructed of spring metal which in the chosen embodiment takes the form of the leaf spring as shown. The spring metal is relatively hard in accordance with conventional practice. The boss 48 which cooperates with the spring is, on the other hand, constructed of synthetic plastic resin as described and has an extremely low coefficient of friction on the surface and in particular the surface of the boss which frictionally engages one side or the other of the configuration 52. Accordingly, even though the configuration may have a relatively well defined angle separating one side 53 from the other side 54, the boss will slide freely over the configuration from one side to the other due to the inherent physical character of the boss thereby to substantially minimize wear at this point which is one portion of the lock mechanism subjected to a maximum amount of movement and wear.

Moreover, by giving the arm 4I of the latch hook member and the central section of the hub 45 the special configurations yand relationships shown, these parts may be pressed together to act as a unit. Because the hub section is of synthetic plastic material and the arm is of metal, an especially snug iit can easily be achieved. The parts can be assembled before being mounted between opposite side walls after which the shafts 35 and 37 can be pressed into engagement with the hub in the relationship shown in the drawings when the mounting plates are applied.

In operation, when the latch hook member is in the Withdrawn or unlocked position, the outermost end is withdrawn from the edge 17 of the door. When the latch hook member is moved to latching or extending position, it moves through a slot 53 in the finger hold 2t) throughout the arc of its movement. For convenience, a side 59 may engage a stop eti formed by a configuration of the side walls 23 and 24 following conventional practice. Similarly, in retracted position, a side 6l of the latch hook member may engage a stop 62. The latch i hook member is manipulated to the different positions as previously mentioned by operation of the knob 36 and in an emergency may be manipulated by rotation of the button 35 making use of a screw slot 53.

In a slightly different form of the invention shown in FIGURES 8 and 9, a latch hook member 30' is shown separate from hub elements 33' which are designed to cooperate with a slightly modified spring 32. In this form of the invention, the shaft 37 of the same configuration as employed in the first-described form of invention has a nonrotatable fit within a hole of similar shape in the latch hook member Sil so that the latch hook member can be rotated by operation of the knob 36 in the usual fashion. In this form, however, the overcenter retention is achieved by a separate operation which is here embodied in the two hub elements 33. These elements are provided in each instance with a hole corresponding in shape and size to the shaft 37 as shown in FIGURE 9. Accordingly, the hub elements 33' have a nonrotatable relationship with respect to the latch hook member 3G so that all are rotated together in response to manipulation of the knob 36.

The hub elements, moreover, are also made of the same synthetic plastic resin material as has been identified in connection with the boss 4S and described in the first noted form of the invention. Each of the hub elements has its outermost end at a location where it lies in engagement with a configuration 52 of the spring 32. Since there are two such hub elements they will be balanced effectively on opposite sides of the latch hook member and make possible employment of a relatively wide spring. It Will be understood, however, that a single one of such elements mounted in the general relationship shown will provide an operable structure. In the position of FIGURE 9 the hub elements 33' act against the spring to hold the latch hook member in withdrawn position. When rotated counterclockwise so that the hub elements are on the opposite side of the conguration 52', the hub elements will hold the latch hook member in an extended position similar t-o that shown in FIGURE 2. Constructed in this fashion the latch hook member can be made as a single metal piece and the hub elements each constructed as a single plastic piece, the combination of which is effected only when the sliding door latch is assembled. The spring 32 is otherwise of the same form and mounted in the same fashion as the spring 32 already described.

While the invention has herein been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices.

Having described the invention, what is claimed as new in support of Letters Patent is:

l. A sliding door latch comprising a support, a rotating assembly comprising a hub member rotatably mounted in the support, said hub member comprising end portions and an intermediate portion of synthetic plastic resin material, and a latch hook member having a nonrotatable engagement with the synthetic plastic resin material of said hub member, a portion of said synthetic plastic resin material having the form of a boss, said boss having an arcuate path of movement during movement of said latch hook member between extended and withdrawn positions, and a spring element on the support, said spring element having a resilient configuration lying in the path of movement of said boss, said boss having an engagement with said configuration between positions on opposite sides thereof corresponding to extended and withdrawn positions of said latch hook member.

2. A sliding door latch comprising a support, a hub member rotatably mounted in the support, a latch hook member of metallic material having a nonrotatable engagement with said hub member, at least a portion of said hub member having a boss thereon at a location spaced axially from the location of said latch hook member, said boss being of synthetic plastic resin material and in non-rotatable engagement with said latch hook member through said hub member, said boss having an arcuate path of movement during movement of said latch hook member between extended and withdrawn positions, and a spring element on the support, said spring element having a resilient configuration lying in the path of movement of said boss, said boss having an engagement with said configuration between positions on opposite sides thereof corresponding to extended and withdrawn positions of said latch hook member.

3. A sliding door latch comprising a support, a hub member rotatably mounted in the support, a latch hook member having a nonrotatable engagement with said hub member, said hub member being of low friction synthetic plastic resin material, a portion of the material of said hub having an outwardly extending position forming a boss at a location beyond the circumference of said latch hook member, said boss having an arcuate path of movement during movement of said latch hook member between extended and withdrawn positions, and a spring element on the support and having a resilient conguration lying in the path of movement of said boss, said boss having a low friction engagement with said coniguration between positions on opposite sides thereof corresponding to extended and withdrawn positions of said latch hook member.

4. A sliding door latch comprising a support, a hub member rotatably mounted in the support, at least one outside end element attached to said hub member in nonrotatable engagement, a latch hook member having an extended position protruding outwardlyr relative to said support and a withdrawn position within the outline of said support, said latch hook member having a noncircular opening therein surrounding said hub member and a recess communicating between said noncircular opening and the exterior of said latch hook member, said hub member being :of low friction synthetic plastic resin material and having a boss extending through the recess to a location beyond the circumference of said hub member, said boss having an arcuate path of movement during movement of said latch hook member between extended and withdrawn positions, and a spring element attached at opposite ends thereof to the support and having a configuration lying in the path of movement of said boss, said boss having a low friction engagement with said coniiguration when said latch hook member is in extended Yand in withdrawn positions.

References Cited in the tile of this patent UNITED STATES PATENTS 2,499,165 Roethel Feb. 28, 1950 2,723,148 Johnson Nov. 8, 1955 3,065,985 DuFour Nov. 27, 1962 

4. A SLIDING DOOR LATCH COMPRISING A SUPPORT, A HUB MEMBER ROTATABLY MOUNTED IN THE SUPPORT, AT LEAST ONE OUTSIDE END ELEMENT ATTACHED TO SAID HUB MEMBER IN NONROTATABLE ENGAGEMENT, A LATCH HOOK MEMBER HAVING AN EXTENDED POSITION PROTRUDING OUTWARDLY RELATIVE TO SAID SUPPORT AND A WITHDRAWN POSITION WITHIN THE OUTLINE OF SAID SUPPORT, SAID LATCH HOOK MEMBER HAVING A NONCIRCULAR OPENING THEREIN SURROUNDING SAID HUB MEMBER AND A RECESS COMMUNICATING BETWEEN SAID NONCIRCULAR OPENING AND THE EXTERIOR OF SAID LATCH HOOK MEMBER, SAID HUB MEMBER BEING OF LOW FRICTION SYNTHETIC PLASTIC RESIN MATERIAL AND HAVING A BOSS EXTENDING THROUGH THE RECESS TO A LOCATION BEYOND THE CIRCUMFERENCE OF SAID HUB MEMBER, SAID BOSS HAVING AN ARCUATE PATH OF MOVEMENT DURING 